In the formation of antenna patterns or patterns of heating or defrosting elements on an automotive glass pane, such as a windshield of an automotive vehicle, it is common to provide a conductive trace or strip which can be rectilinear and which can constitute a collector trace, busbar or the like in electrical connection with a plurality of other traces or wires. For example, the collector trace or busbar may run along one of the sides of the windshield or rear window of the automotive vehicle in a more or less upright manner whereas the other traces connected to this busbar or collector trace extend parallel to one another more or less horizontally.
The process can be used for heating the windshield or defrosting and deicing purposes or can serve as conductors forming parts of an antenna element or constituting antenna elements.
The collector trace or busbar is usually straight and can extend substantially the full length of an edge of the pane, e.g. a lateral edge thereof.
It is known that the trace can be built up or reinforced galvanically, i.e. by the electrodeposition of metal upon the conductive band.
In a conventional apparatus for this purpose as described in Japanese published application 60 159 194, the anode which is connected with the cathode to an electroplating current source, is constituted as a tampon which is impregnated with the electrolyte. This anode is brought into contact with the conductive trace and is moved slidingly therealong. This, of course, requires a service person so that this method of reinforcing a conductive trace is labor intensive. In fact, it cannot be automated in a practical manner.
However, it also has not been found to be desirable for other reasons as well. For example, the coating thickness of the reinforcement process depends upon the training and skill of the service person guiding the anode tampon along the trace. It cannot, therefore, be guaranteed that the deposit will be uniform or satisfactory.
Tampon electroplating, therefore, has found most interest in repair of electroplated objects (see Galvanotechnik 1982, pages 120 ff).
For other purposes, i.e. other purposes than the electroplating reinforcement of an elongated conductive trace on a glass pane, apparatus has been developed which provides a chamber which can be placed upon an electroplatable substrate (see German printed application DE-AS No. 16 21 143). Here the cathodes are constituted by the chamber wall. The anode in this arrangement, at least at its lower portion, is formed as a rod.
This results in potential and current density gradient and field conditions which prevent effective use of the apparatus for the uniform electroplating of conductor traces. The electrolyte is fed along the anode into the chamber and is carried away in a corresponding manner. This flow path and the escape of the electrolyte from the chamber and the fact that it can run onto the workpiece in an uncontrolled manner makes this system especially inconvenient for electroplating upon an elongated conductive trace on a glass pane, especially when the thickening of the trace by electrodeposition should be or must be effected automatically.
In various electrodeposition processes, moreover, it is necessary after deposition of material and even before such deposition or in intermediate phases between electrodepositions, to effect rinsing of the surface upon which the electrodeposit is to be formed or has been formed with water or other running liquids. In the past this had to be done in special apparatus and this, of course, was detrimental to mass production use of earlier techniques.